I was unable to find any support tickets after September 2017 with the email address you signed up to the community forum with, but if you PM me the other email address I can look into it.
The mesh devices won’t be shipping until October 2018.
For SIM card or device cloud charges, you are normally sent an email with the billing details. If you require an official pdf invoice, you currently have to request one using the support form (Shipping, Returns and Pricing, then I need an invoice for my subscription service.). Make sure you do so using the same email address as the account. Unfortunately this has to be done manually right now, so there’s no way to automatically get a pdf invoice every month but it is something that is planned for the future.